Rotoplane platform energy source

ABSTRACT

An educational/experimental unit demonstrating principles of mechanical energy storage and conversion comprises a platform base which is rotatable and is driven by at least one propeller supported from the base. The base allows multiple orientations of the propeller and the use of multiple propellers to provide an effective series of experiments for demonstrating the principles involved.

United States atent [191 Montgomery et a1.

ROTOPLANE PLATFORM ENERGY SOURCE Inventors: Marshall A. Montgomery, Pleasant Hill; Herbert D. Thier, Moraga, both of Calif.; John B. Ortei, North Revere, Mass.

American Science & Engineering Inc., Cambridge, Mass.

Filed: June 15, 1972 Appl. No.: 263,107

Assignee:

U.S. Cl. 35/19 R, 46/47 Int. Cl. G091) 23/08 Field of Search..... 35/19 R, 34; 46/47; 108/94,

108/150; D44/10 E, 10 F; D9/185; 272/31 R References Cited UNITED STATES PATENTS 10/1934 Clark D44/10 F UX Feb. 5, 1974 2,027,162 1/1936 Goldman 46/76 R 2,178,014 10/1939 Brown 46/44 UX 2,532,571 12/1950 Reeves 272/31 R 3,424,110 1/1969 Toot D9/l85 UX 3,647,104 3/1972 Goings D9/l85 UX Primary Examinerl-larland S. Skogquist Attorney, Agent, or Firm-Charles Hieken; Jerry Cohen 5 7] ABSTRACT An educational/experimental unit demonstrating principles of mechanical energy storage and conversion comprises a platform base which is rotatable and is driven by at least one propeller supported from the base. The base allows multiple orientations of the propeller and the use of multiple propellers to provide an effective series of experiments for demonstrating the principles involved.

10 Claims, 2 Drawing Figures ROTOPLANE PLATFORM ENERGY SOURCE BACKGROUND OF THE INVENTION The invention described herein was made in the course of or under a grant from the National Science Foundation, an agency of the United States Government.

The present invention relates to educational equipment for demonstrating the principles of mechanical energy storage and conversion. Reference is made to the copyrighted book Energy Sources prepared by the Science Curriculum Improvement Study, copyrighted in 1971 by The Regents of the University of California Berkeley California, first printing June 1971 and published by Rand McNally and Company, PO. Box 7600, Chicago, Ill. 60680, the said book being incorporated herein by reference as though written out at length herein and including all text and illustrations therein.

The above cited book provides series of useful lesson plans for a platform base which is mounted to a rotate and is driven by propellers which are energized through elastic motors e.g., a simple rubber band.

Such equipment has the important and related criteria of being lightweight, compact, inexpensive and capable of repeated rough handling by children and affording ease and reliability of use by children.

It is the object of the invention to provide equipment meeting the foregoing criteria.

SUMMARY OF THE INVENTION A platform base supports islands which define channels between them. The channels intersect at various points and are of sufficient width to give side frictional support to long rod like, elongated member, supports hereafter described. The platform has one raised central island which fits over a post which supports the platform for rotation. The post can be accommodated in a tubular bearing for stable rotational support.

Preferably, the platform and its raised islands are made from a single thermoplastic sheet which is pressed to the desired configuration or case or injection molded. The sheet is made less than 0.050 inches thick and the spaces under the islands are empty to minimize weight and allow the platform to rotate in response to a light driving force.

The channels intervening between the islands include radial channels coming from the center to the exterior of the platform and tangential channels crossing the radial channels and not themselves intersecting the center.

The outer edge of the platform has a regular polygonal geometric form preferably a hexagon in a preferred and distinctly advantageous embodiment and the form has corners. The tangential channels run between corners and the radial channels run out through both corners and sides between corners. The regular arrangement of channels and exterior edge gives the student a means of identifying distinct channel configurations and the spacing of islands also affords a rough length indication to the student.

The island arrangement affords multiple side supports consistent with a tolerance for many crossing channels.

The channels are designed to accommodate propeller supports. These supports are preferably rectangular dowels or strips. They are enclosed at their ends by sheaths which are of common design for the two ends and comprise molded plastic sheathing portions and raised posts supporting a bearing channel which runs parallel to the rod support. A pin can be passed through one of the bearings and bent at ends to hold a propeller which is mounted on such pin and to hold one end of an elastic band (rubber band). The other end of the rubber band can be wrapped around the sheathed post at the other end of the support rod. A rod can be made of molded plastic with integral raised bearing posts at its ends to eliminate the need for separate sheath elements and assembly. This alternative construction can also eliminate extra width associated with sheaths.

The rod is placed by the student in a channel of the platform. He winds the rubber hand using the conveniently large handle provided by the propeller itself, records the number of turns and lets go and watches as the propeller spins and whirls the platform about its r0- tatable support. He counts the number of rotations of the platform itself and relates that to the number of turns originally given to the rubber band (i.e., the energy stored) and the effective length of the rod and its orientation with respect to the platform.

Multiple propellers can be used on a given platform and each of the propellers can have a wide variety of orientations of effective length and/or direction. They can be radially or tangentially aligned and various placements can extend out to a variable distance from the center with variable effective angles. The multiple propellers can be arranged for additive or opposing driving effects in whole or in part.

Numerous other features, objects and advantages of the invention will become apparent from the following specification when read in connection with the accompanying drawing in which:

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an exploded top view of the platform and one corresponding support rod and propeller therefore;

FIG. 2 is a sectional side view cut as indicated by the sectional arrows A-A in FIG. 1 and it is similarly exploded and shows the elastic band which is partly omitted from the top view of FIG. 1 for clarity of illustration.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS With reference now to the drawing, and more particularly FIG. 1 thereof, there is shown an exploded view of a rotoplane rotatable platform base support 10 with raised islands 11 26 thereon in the lower half of FIG. 1 and the upper half of FIG. 1 has similar arrangement of islands (unnumbered) which are a mirror image matching of the numbered islands in the lower half of the platform.

The channels intervening between the raised islands include the channels lA-TB, 2A-2B, 3A-3B, 4A-4B, SA-SB, 6A-6B, 7A-7B, 8A-8B, SBA-9B. Additional channels are seen to be defined, but these are not numbered. Of the numbered channels, lA-lB and 2A-2B are radial channels and the other numbered channels are tangential. It is seen in the lower half of FIG. 1 that major intersections 28, 29, 30, 31, 32 and 33 are formed by intersecting channels.

Looking more closely at intersection 28, it is seen that at the intersection there are shoulders 21A and 2113 on the island 21 which are diagonally opposite shoulders 12A and 123 on island 12. Similar arrange ments are utilized at intersection 29 and two corresponding unnumbered intersections in the upper half of FIG. 1. These widened-out portions along the channel lengths are to provide tight fitting frictional support to the sheath members described below in multiple orientations. In the case of intersection 28 a sheath member could be on the end of an elongated member which runs along channel 6A-6B or 3A-3B and be accommodated. The long portions of channel between such widened-out channel'portions at the channel intersections provide good side frictional support for the central unsheathed rod form elongated members described be low.

In the right side of the exploded views of FIGS. 1 and 2 is shown the propeller 100 mounted on a rod support 110 via a sheath I14 and a pin shaft 102. The pin shaft 102 passes through a channel 103 which is on a first post 1 15 on sheath 114. A similar sheath 112 is used at the other end of the rod 110, the sheath 112 having a second post 113 similar to post 1 15. A rubber band 106 can be hooked on to a curve 104 of pin 102 and post 113. The propeller 100 has a simple right angle turn between its two blade halfs and it engages the pin 102 with enough side support so that as a propeller is wound it causes the pin 102 to turn and this in turn winds up rubber band 106. When the students hand is released from winding up the propeller 100, rubber band 106 drives the propeller. The propeller acts as an air foil in transmitting drive to the sheath 114 and the rod 110 drives by the platform 10 by reaction force.

The platform 10 is mounted for rotation on a post 200 which is in turn held in a tubular plastic bearing 202. This plastic bearing can be the plastic syringe which is a component part of the Stopper-Popper kinematics educating device sold by American Science and Engineering, Inc., of Cambridge Massachusetts, which is supportable upright from a wide platform in one of its available adjustments, or other plastic tubular mem ber made up for the purpose. In any such case the tubular bearing should have a wide base to stably support the rotating platform and prevent tipping as a result of the experiment.

It is evident that those skilled in the art may now make numerous uses and modifications of, and departures from the specific embodiments described herein without departing from the inventive concepts herein. Consequently, the invention is to be construed as embracing each and every novel feature and novel combination of features present in, or possessed by the apparatus and techniques herein disclosed and limited solely by the scope and spirit of the appended claims.

What is claimed is:

1. An educational/experimental apparatus for demonstration of principles affecting mechanical energy storage and conversion comprising, in combination,

means defining a rotatable platform base with raised islands thereon defining a pattern of multiple intervening channels therebetween,

means for mounting said base to rotate and constructed and arranged to fit a rotational support,

and means defining at least one elongated driving member with an elastic motor thereon in which mechanical energy may be stored and released,

the said channels frictionally engaging each elongated member placed therein,

whereby reaction driven rotation of said base is provided in a variety dependent on the placement of said members in said channels and the energy stored in said members.

2. Apparatus in accordance with claim 1 and further comprising means defining said rotational support.

3. Apparatus in accordance with claim 1 wherein the platform base has the form of a polygon, with at least one radial channel running through a point of said polygon and one radial channel running through a side of said polygon and at least one tangential channel connecting two points of said polygon.

4. Apparatus in accordance with claim 3 wherein said polygon is a hexagon having tangential channels running from point to point along the bases of the six triangles at the ends of the hexagon and having two radial channels running from the rotational center of the platform to two points of the hexagon and intersecting two of said triangle bases.

5. Apparatus in accordance with claim 4 further comprising six channels running along the six hexagon edges, all of said tangential channels being open at two ends thereof.

6. Educational/experimental apparatus in accordance with claim 1 wherein each said elongated member comprises a raised post thereon mounting said elastic motor.

7. Educational/experimental apparatus in accordance with claim 6 wherein each said elongated member comprises two end posts thereon,

one of said posts comprises a propellor shaft mounted thereon in a bearing extending parallel to the direction of elongation of said member,

a propellor mounted on said shaft,

an elastic band connected between said shaft and the second of said posts and arranged to store energy as said propellor and shaft are turned in one direction and release energy by turning the propellor and shaft in the other direction to drive the rotatable platform base.

8. Educational/experimental apparatus in accordance with claim 7 and further comprising end sheaths fitted on the ends of said member and mounting said posts.

9. An educational/experimental apparatus in accordance with claim 8 wherein said channels have widened-out portions along their lengths for fitting said end sheaths.

10. Apparatus in accordance with claim 9 having channel intersections wide enough to fit said sheaths regardless of particular channel alignment of the rod, the channels being radial and tangential and affording a multiplicity of effective lengths and orientations of the elongated member. 

1. An educational/experimental apparatus for demonstration of principles affecting mechanical energy storage and conversion comprising, in combination, means defining a rotatable platform base with raised islands thereon defining a pattern of multiple intervening channels therebetween, means for mounting said base to rotate and constructed and arranged to fit a rotational support, and means defining at least one elongated driving member with an elastic motor thereon in which mechanical energy may be stored and released, the said channels frictionally engaging each elongated member placed therein, whereby reaction driven rotation of said base is provided in a variety dependent on the placement of said members in said channels and the energy stored in said members.
 2. Apparatus in accordance with claim 1 and further comprising means defining said rotational support.
 3. Apparatus in accordance with claim 1 wherein the platform base has the form of a polygon, with at least one radial channel running through a point of said polygon and one radial channel running through a side of said polygon and at least one tangential channel connecting two points of said polygon.
 4. Apparatus in accordance with claim 3 wherein said polygon is a hexagon having tangential channels running from point to point along the bases of the six triangles at the ends of the hexagon and having two radial channels running from the rotational center of the platform to two points of the hexagon and intersecting two of said triangle bases.
 5. Apparatus in accordance with claim 4 further comprising six channels running alonG the six hexagon edges, all of said tangential channels being open at two ends thereof.
 6. Educational/experimental apparatus in accordance with claim 1 wherein each said elongated member comprises a raised post thereon mounting said elastic motor.
 7. Educational/experimental apparatus in accordance with claim 6 wherein each said elongated member comprises two end posts thereon, one of said posts comprises a propellor shaft mounted thereon in a bearing extending parallel to the direction of elongation of said member, a propellor mounted on said shaft, an elastic band connected between said shaft and the second of said posts and arranged to store energy as said propellor and shaft are turned in one direction and release energy by turning the propellor and shaft in the other direction to drive the rotatable platform base.
 8. Educational/experimental apparatus in accordance with claim 7 and further comprising end sheaths fitted on the ends of said member and mounting said posts.
 9. An educational/experimental apparatus in accordance with claim 8 wherein said channels have widened-out portions along their lengths for fitting said end sheaths.
 10. Apparatus in accordance with claim 9 having channel intersections wide enough to fit said sheaths regardless of particular channel alignment of the rod, the channels being radial and tangential and affording a multiplicity of effective lengths and orientations of the elongated member. 